JP4439943B2 - Method for manufacturing semiconductor device - Google Patents

Description

  The present invention relates to a stable carbon nitride composition that can be formed at a low temperature and a method for manufacturing the same.

  The present invention further relates to an article such as a food or beverage container or an electronic component coated with the carbon nitride composition of the present invention. Further, a thin film transistor (TFT) having the carbon nitride composition as an interlayer insulating film, a base film, a gate insulating film, and other insulating films, a display device having the thin film transistor and a light emitting element, a liquid crystal display device, and other display devices and the like It relates to a manufacturing method.

  Conventionally, research has been conducted in a wide range of fields, taking advantage of the characteristics of carbon nitride compositions. Typically, there is a field related to a technique of coating various protective articles for protecting various articles from external damage and reducing frictional resistance. For example, a CN film in which a hydrogen content is reduced and a single bond of nitrogen and carbon is increased by using a secondary or tertiary amine at room temperature by a plasma CVD method (see Patent Document 1) or a sputtering method. In this way, a CN film is formed (see Patent Document 2).

Research is also being conducted in the semiconductor field. In recent semiconductor fields, with the miniaturization, a high dielectric constant of an insulating film is a cause of circuit delay, and an attempt has been made to use a carbon nitride composition, which is expected to have a low relative dielectric constant, as an insulating film. For example, as an insulating film used in a semiconductor element, reactive sputtering and hydrogen plasma treatment are performed on a silicon substrate to form an amorphous carbon nitride film composition (see Patent Document 3).
JP-A-9-255314 Japanese National Patent Publication No. 11-504753 Japanese Patent Laid-Open No. 11-238684

  However, conventional carbon nitride compositions have limitations on the film forming method and characteristics. For example, when used as a protective film, it is necessary to satisfy the conditions that the material of the substrate (article) to be deposited and the temperature at which the carbon nitride composition is formed conflict. That is, the stability of the carbon nitride composition has decreased as the film forming temperature is lowered with the heat resistant temperature of the film forming substrate. As a result, the degree of freedom of the method for forming the carbon nitride composition has been limited by the material of the substrate to be formed. In particular, in the case of a resin material such as a PET bottle having a low softening point, it is difficult to set a low film formation temperature although it is desired to avoid a high film formation temperature from the material. As a result of further increasing the film formation temperature, it took time to set the temperature to a certain high temperature or to cool it.

  Accordingly, an object of the present invention is to efficiently form a carbon nitride composition having high gas barrier properties, high stability, high covering properties and high adhesiveness despite the fact that the film is formed at a low temperature. Specifically, PET bottles, other food or beverage containers having the carbon nitride composition of the present invention, highly durable and low frictional resistance CD-ROMs, magnetic heads, photosensitive drums, and other electronic components ( Parts) and a method for manufacturing the same).

  In addition, an insulating film in a semiconductor device typified by a conventional thin film transistor has low stress relaxation property and low step coverage because of a low hydrogen concentration in the film. In particular, as the formation temperature of the insulating film was lowered, hydrogen in the film was easily released, and hydrogen was released in a subsequent heating process, resulting in film peeling and adhesion. Therefore, the degree of freedom in forming the insulating film is limited by the material of the semiconductor element and the material of the display element provided on the semiconductor element.

  For example, when forming an organic light emitting layer (a light emitting layer having an organic compound), forming an electrode on the organic light emitting layer, and forming an insulating film as a protective film on the electrode so as not to deteriorate the organic light emitting layer, the forming temperature There was a possibility that the organic light emitting layer deteriorated as the value of the height increased. In particular, the organic light emitting layer has a problem of deterioration due to moisture and oxygen, and the release of hydrogen and oxygen from the protective film and the interlayer insulating film has been a problem.

  Furthermore, in recent years, methods for forming a light and thin display device by forming semiconductor elements on a flexible substrate have been studied. An organic resin material is often used for a flexible substrate, and it was desired to avoid forming an interlayer insulating film, a protective film, a base insulating film and a gate insulating film on such a substrate at a high temperature.

  Accordingly, it is an object of the present invention to use the carbon nitride composition having high coverage and adhesion and capable of being formed at a low temperature as an insulating film for all semiconductor devices and display devices.

  In view of the above problems, the carbon nitride composition of the present invention is formed at a film forming temperature capable of containing 30 to 45 atomic% of hydrogen, for example, 100 ° C. or lower, preferably 50 ° C. or lower, more preferably 20-30 ° C. However, it is characterized by maintaining stability and adhesion.

  The carbon nitride composition of the present invention contains hydrogen, nitrogen and carbon, and the composition ratio of hydrogen is 30 to 45 atomic%, preferably 35 to 40 atomic%. Then, the total composition ratio of nitrogen and carbon other than hydrogen is in the range of 55 to 70 atomic%. Among the ranges, the composition ratio of nitrogen to carbon is 10 to 20 atomic% for nitrogen and 40 to 50 atomic% for carbon when a stable gas such as nitrogen is used as the reaction gas. Further, when a gas that is easily decomposed, such as a nitride gas, is used, the composition ratio is 35 to 45 atomic% for nitrogen and 15 to 20 atomic% for carbon. Needless to say, the above range can be assumed on the assumption that the composition ratio values are 100 atomic% in total.

In the present invention, since a carbon nitride composition contains a large amount of hydrogen, a carbon nitride composition is formed by vapor phase growth using a mixture of a carbide gas that is easily dissociated by plasma and nitrogen or a nitride gas. It is characterized by doing. The vapor phase growth method may be any method that dissociates or separates a carbide gas by a plasma generating means. For example, plasma such as a high frequency discharge plasma CVD method, a microwave plasma CVD method, an electron cycloton resonance (ECR) plasma CVD method, or the like. Any of the CVD methods can be used. The carbide gas may be a substance that can be expressed by CxHy, for example, C ₂ H ₂ or C ₂ H ₄ may be used, and the nitride gas may be a substance that can be expressed by NxHy, for example, NH ₃ may be used.

  Further, the present invention employs a sputtering method capable of forming a carbon nitride composition containing a large amount of hydrogen, for example, a sputtering method in which nitrogen or ammonia gas, hydrogen or the like is mixed into a sputtering gas and graphite carbon is used as a target. Can do. That is, the present invention is characterized by the hydrogen concentration of the carbon nitride composition, and is not limited to the production means.

  Such a carbon nitride composition having a high hydrogen concentration has a high stress relaxation property, and has a good coverage even on a film-formed substrate having a curved surface or other shapes.

  Further, as one of the stability judgments of the carbon nitride composition, the hydrogen release amount is evaluated. As a result, the carbon nitride composition of the present invention was formed at a low temperature of 100 ° C. or less, and despite being rich in hydrogen, it was 450 ° C. to 500 ° C. or more, and further around 600 ° C. (about 450 ° C. to 600 ° C. ) Is characterized by extremely low hydrogen release even when heated in the

  The carbon nitride composition of the present invention that does not release hydrogen even when heated in this manner has high stability, low reactivity with the substance in contact with it, and is suitable as a protective film. Moreover, it is thought that not releasing hydrogen having the smallest atomic radius means that the amount of gas passing through the carbon nitride composition is extremely small, and the gas barrier property is very high.

  According to the present invention as described above, when the carbon nitride composition is used as a protective film, the degree of freedom of the substrate on which the film is formed is increased, and the film can be formed particularly on an organic resin material typified by plastic. An article coated with the carbon nitride composition of the present invention is excellent in wear resistance and friction characteristics, and as a result, the life of the article can be improved.

  In particular, since it has a high gas barrier property, it is preferably used as a protective film for containers for food and drinking water. In particular, the carbon nitride composition of the present invention is preferably used for a protective film of a PET bottle, a packaging container for foodstuffs, or a packaging bag. Current food packaging containers and bags are coated with an aluminum material in order to enhance gas barrier properties, and therefore, food products cannot be confirmed at the time of purchase. On the other hand, since the carbon nitride composition of the present invention has translucency, it can be expected to confirm foodstuffs at the time of purchase and to increase consumers' willingness to purchase.

  The carbon nitride composition of the present invention is preferably in an amorphous state or a polycrystalline state depending on the purpose.

  The present invention also provides a thin film transistor including at least one of an interlayer insulating film, a base film, a protective film, and other insulating films having the carbon nitride composition as described above, and a display device (including a display module) having the thin film transistor. It is characterized by.

  As described above, the carbon nitride composition of the present invention can be formed at a film forming temperature of 100 ° C. or lower, preferably 50 ° C. or lower, more preferably 20 to 30 ° C. Is suitable.

  In the case of a display device having a light-emitting element, the carbon nitride composition of the present invention can be used for the interlayer insulating film, the gate insulating film, or the base film, and the influence of moisture on the organic light-emitting layer can be reduced. In particular, it is suitable as a protective film on the cathode of a display device having a light emitting element.

  The carbon nitride composition of the present invention can be formed at a film forming temperature capable of containing 30 to 45 atomic% of hydrogen, for example, 100 ° C. or less, preferably 50 ° C. or less, more preferably 20 to 30 ° C. . Therefore, it is possible to form a film without considering the properties of the substrate to be deposited, and it is not necessary to raise the film forming temperature to a certain constant temperature or to cool it. improves.

  The hydrogen ratio of the carbon nitride composition of the present invention is 30 to 45 atomic%, preferably about 35 to 40 atomic%, and has high stress relaxation properties. Therefore, the carbon nitride composition can be formed uniformly without film peeling even if the shape of the substrate to be deposited is not only planar but also has a curved surface.

  Furthermore, the carbon nitride composition of the present invention has a very low hydrogen release amount and high stability. As a result, a highly adhesive film that is difficult to peel off can be obtained. In particular, when the carbon nitride composition is used as a protective film, the carbon nitride composition can be formed on the deposition target substrate without using a buffer layer.

  In addition, a thin film transistor and a display device including the above-described carbon nitride composition of the present invention can be provided.

  According to the present invention as described above, an inexpensive carbon nitride composition having stable durability and suitable for mass production can be provided. Moreover, the carbon nitride composition formed according to the present invention can be applied to all fields.

  Embodiments of the present invention will be described below with reference to the drawings. However, the present invention can be implemented in many different modes, and it is easy for those skilled in the art to make various changes in form and details without departing from the spirit and scope of the present invention. Understood. Therefore, the present invention is not construed as being limited to the description of this embodiment mode. Note that in all the drawings for describing the embodiments, the same portions or portions having similar functions are denoted by the same reference numerals, and repetitive description thereof is omitted.

(Embodiment 1)
In this embodiment, a method for forming a carbon nitride composition will be described with reference to FIG.

  In the plasma CVD apparatus shown in FIG. 1, a film forming chamber 100 is provided with a grounded stage 102 for fixing a film formation substrate 101 and a vertical mechanism 103 for moving the stage up and down. Note that since the stage has a function of an electrode, the stage is preferably formed using a metal-containing material. Of course, the stage and the electrode may be arranged respectively. Note that the deposition target substrate is an article on which a carbon nitride composition is formed or a substrate on which a semiconductor element typified by a thin film transistor is formed.

  A counter electrode 104 is disposed at a position facing the film formation substrate via an electrode (shower head) 105 provided with gas ejection holes (holes). For example, the counter electrode has a stainless material, and the showerhead has an aluminum material. The number of ejection holes may be set as appropriate. In addition, a plurality of shower heads may be arranged in an overlapping manner, the number of holes is different on the substrate side and the counter electrode side, or the diameter of the holes is reduced toward the substrate side (that is, the film formation substrate side) It is preferable to allow the reaction gas to diffuse uniformly. Furthermore, you may provide the electrode which served as the shower head function and the electrode which provided the ejection hole in the conductor which has a hollow.

  Further, in order to control the temperature, a means 110 for controlling the temperature such as a heating means or a cooling means (refrigerant) is provided on the counter electrode 104. As the cooling means, for example, cooling water flowing through the drawn piping can be used, and the temperature of the counter electrode can be rapidly and gradually cooled.

  A high frequency power source 109 is connected to the counter electrode 104, and a high frequency (for example, 13.56 MHz) for generating plasma is applied. Further, a matching box for adjusting and controlling the frequency and phase may be provided.

A hole (supply hole) through which a source gas is supplied is provided at a predetermined position (preferably the upper surface) of the film formation chamber 100, and a plurality of source gas supply means (for example, first to third gas supply means 106). To 108) are supplied in a mixed state. Alternatively, a cleaning gas such as NF ₃ or O ₂ may be supplied from any of the gas supply means, and film formation and cleaning may be performed alternately.

  In addition, a hole for supplying a gas is provided in a part of the counter electrode 104, and further, a source gas is supplied to the vicinity of the deposition target substrate through the hole of the shower head. At this time, the distance d between the counter electrode 104 and the deposition target substrate 101 is fixed to several cm (preferably 3 to 5 cm) by the vertical mechanism. As a result, the generated plasma can be kept within a limited range, and film formation can be performed efficiently.

As the source gas of the present embodiment, a carbide gas gas such as acetylene (C ₂ H ₂ ) or ethylene (C ₂ H ₄ ) and a nitride gas such as nitrogen (N ₂ ) or ammonia (NH ₃ ) are used. Use. In particular, since acetylene has a triple bond of carbon, it can be expected that the reaction is higher than that of methane (CH ₄ ). The flow rate of the raw material gas may be appropriately set in the range of 20 to 50 sccm for the carbide gas gas and 150 to 350 sccm for the nitrogen or nitride gas gas.

  Further, a rotary pump 120 and a dry pump (which may be a turbo pump) 121 are provided as exhaust means for exhausting gas at a predetermined position (preferably the lower surface) of the film formation chamber 100. In the present embodiment, a plurality of exhaust means are provided, but one may be used. The pressure in the film forming chamber is controlled by the evacuation means, and is appropriately set within the range of 0.1 to 1 Torr.

  Further, it is preferable to provide a rectifying plate 122 around the stage 102 of the film formation chamber 100. With the current plate, it is possible to keep the efficiently generated plasma in a limited reaction region. Furthermore, it can be used to control the flow rate and direction of the gas flowing into the exhaust means through the rectifying plate.

  In such a film formation chamber, a film formation substrate is placed on a stage to form a carbon nitride composition. It is preferable to form a carbon nitride composition on a substrate placed on a stage to be grounded because the plasma charge is small. However, the carbon nitride composition of the present invention can be formed even in a state where the film formation substrate is disposed on a stage to which a high frequency power source is connected. In this case, a self-bias can be applied to the substrate, and the hardness of the carbon nitride composition can be further controlled.

  Even when a carbon nitride composition is formed on either a substrate placed on a grounded stage or a substrate to which a high frequency power supply is connected, the gas flow rate, pressure, and applied voltage are controlled. As a result, the hardness of the carbon nitride composition can be gradually increased (continuously or stepwise) or decreased. As a result, the adhesion can be improved.

  The carbon nitride composition is formed at 100 ° C. or lower, preferably 50 ° C. or lower, more preferably 20-30 ° C., using the gas phase reaction film forming apparatus as described above. More specifically, the carbon nitride composition can be manufactured without heating the film formation chamber. However, it is conceivable that the electrode to which the high frequency is applied is heated to some extent.

  Since the carbon nitride composition of the present invention can be formed at a low temperature, various substrates can be coated with the carbon nitride composition without considering the properties of the substrate to be deposited, or as an insulating film of a semiconductor element. Can be formed. In addition, since it is not necessary to raise the film formation temperature to a certain level or to cool it, the film formation efficiency is improved.

  The carbon nitride composition formed as described above has a high stress relaxation property because it contains 30 to 45 atomic%, preferably 35 to 40 atomic% of hydrogen. As a result, it is possible to form a carbon nitride composition uniformly even if the substrate to be deposited has a curved surface as well as a flat shape without peeling off the film.

  When the carbon nitride composition of the present invention is used as a protective film or an insulating film of a semiconductor device, the carbon nitride composition and other films (for example, a nitride film or an oxide film) may be stacked. Good. Further, since the carbon nitride composition of the present invention has high adhesion, it is possible to form a film on a deposition target substrate without using a buffer layer.

  According to the present invention, an inexpensive carbon nitride composition having stable durability and suitable for mass production is formed at a low temperature of 100 ° C. or lower, preferably 50 ° C. or lower, more preferably 20 to 30 ° C. be able to.

(Embodiment 2)
In this embodiment, a case where a carbon nitride composition is formed on a PET bottle as a protective film for a specific product will be described.

  As shown in FIG. 2A, a plastic bottle 201 serving as a film formation substrate is fixed to a chamber 203. Specifically, a chamber 203 divided into an upper part and a lower part is prepared, and an external electrode 202 is provided on the surface that comes into contact with the plastic bottle. Then, a plastic bottle is installed in the lower chamber, and then the upper chamber is covered, and the plastic bottle is fixed to the chamber 203.

  The PET bottle 201 is formed of a material selected from a thermoplastic resin typified by polyethylene, polystyrene, polymethylpentene, vinyl chloride resin, polyethylene terephthalate, a thermosetting resin typified by a phenol resin, and the like.

  Thereafter, a pipe to which the source gas is supplied is inserted from above the PET bottle. Note that the pipe for supplying the gas is preferably formed using a metal-containing material in order to serve as the internal electrode 204. In the present embodiment, first and second gas supply means 206 and 207 are connected to the pipe, and the mixed source gas is supplied into the PET bottle through the pipe. In addition, the practitioner may install the gas supply unit as appropriate, and the gas supply unit may be provided singly or three or more. Furthermore, in order to supply gas uniformly to the inner surface of the PET bottle, it is preferable that a plurality of gas supply holes 210 are provided on the side surface of the pipe. As in the first embodiment, a rotary pump 211 and a dry pump 212 are provided as exhaust means for exhausting gas.

  The external electrode 202 is disposed on a side surface in contact with the plastic bottle 201 in the chamber 203, and a high frequency power source 209 is connected to the internal electrode 204. A high frequency of 13.56 MHz is applied from the high frequency power supply 209 to generate plasma. Carbon ions, nitrogen ions, and hydrogen ions are attracted to the inner surface of the PET bottle close to the external electrode, and the carbon nitride composition is coated by about 10 nm to 100 nm.

  2B and 2C show a case where the shape of the internal electrode (pipe) in FIG. 2A is different, and the other external electrodes and the like are the same as those in FIG. In FIG. 2B, an internal electrode serving as an axis and an electrode extending toward the bottom (bottom surface) of a plastic bottle provided on the internal electrode are provided. The internal electrode serving as the shaft and the electrode provided on the internal electrode are fixed so that their angles are about 10 to 30 degrees, or designed so as to expand due to the pressure when the source gas is blown out. That's fine. Further, like the internal electrode shown in FIG. 2C, an internal electrode serving as a shaft and a plurality of electrodes that spread toward the lower surface of the PET bottle provided on the internal electrode may be provided at a plurality of locations. Such a shape of the internal electrode can more uniformly coat the PET bottle.

  The shape of the internal electrode does not have to be rod-shaped (cylindrical), and may be formed along the surface shape of a curved plastic bottle. Furthermore, in the CVD apparatus shown in FIGS. 2A to 2C, the internal electrode may be rotated to form a uniform protective film.

  As described above, in the present embodiment, a single plastic bottle has been described. However, in order to improve mass productivity, it is conceivable to coat a plurality of plastic bottles simultaneously.

  In the present embodiment, coating is performed with the opening of the plastic bottle facing upward, but coating may be performed with the opening facing downward.

  As described above, the carbon nitride composition of the present invention and the surface of the PET bottle are sufficiently adhered to each other, further contain a relatively large amount of hydrogen, and have high stress relaxation properties, thereby reducing coating defects (cracks, etc.) due to deformation of the base plastic. it can.

  The PET bottle coated in this way has a high gas barrier property against oxygen and carbon. And since it is chemically stable, it does not have a bad influence on the drinking water in a PET bottle.

(Embodiment 3)
In this embodiment, the case where a carbon nitride composition is formed as a protective film over a plurality of deposition target substrates will be described.

  First, the case where a film is formed on a substrate having a flat shape will be described. The CVD apparatus shown in FIG. 3 is the same except that the stage can be rotated in the CVD apparatus of FIG. That is, the stage 102 is disposed in the film formation chamber 100, and a plurality of film formation substrates are fixed on the stage by a holder (not shown). The stage has a circular shape, and a rotation shaft 401 is provided at the center so that a fixed film formation substrate can be rotated. A space is provided at the center of the rotation shaft, and the stage 102 is grounded through the space.

  Thus, by coating the protective film while rotating a plurality of deposition target substrates, a uniform protective film can be formed, which is suitable for mass production.

  Unlike FIG. 3, FIG. 4 shows a CVD apparatus for coating a protective film on both surfaces (upper surface and side surface) in a state where a columnar substrate is fixed vertically.

  As shown in the cross-sectional view of FIG. 4A, a columnar deposition target substrate 101 is fixed on a stage 102 so as to be perpendicular to the stage by a holder (not shown). In this case, the pair of electrodes 301 and 302 to which a high frequency is applied from a power source is arranged to be perpendicular to the stage. Of course, the pair of electrodes 301 and 302 may be arranged parallel to the stage. Further, a heating unit or a cooling unit may be provided to control the temperature of the pair of electrodes 301 and 302. A high frequency power source is connected to one of the pair of electrodes 301 and 302, and the other is grounded. In FIG. 4, the high frequency power source 109 is connected to the electrode 301, and the electrode 302 is grounded.

  Further, as shown in the top view of FIG. 4B, the pair of electrodes 301 and 302 are arranged so as to be perpendicular to the deposition target substrate so that the reaction gas is distributed throughout.

  In the case of the CVD apparatus shown in FIG. 4, it is necessary to set the distance between the film formation substrate, that is, the stage and the gas supply hole (shower head) to be equal to or higher than the height of the film formation substrate. The arrangement and shape of the pair of electrodes 301 and 302 may be devised. For example, the shape of the pair of electrodes 301 and 302 may be curved into a semicircle, or two or more electrodes may be arranged to surround the deposition target substrate. Moreover, you may form a carbon nitride composition, arrange | positioning a rotating shaft and rotating a stage.

  As described above, the carbon nitride composition of the present invention can be produced using various CVD apparatuses, and can be mass-produced efficiently.

(Embodiment 4)
In this embodiment, a method for manufacturing an active matrix substrate using a carbon nitride composition for an insulating film such as an interlayer insulating film will be described with reference to FIGS. Note that a plurality of TFTs are formed over the active matrix substrate, but a driver circuit portion having an n-channel TFT and a p-channel TFT and a pixel portion having an n-channel TFT will be described.

As shown in FIG. 6A, a single-layer film or a stacked film of an insulating film such as a silicon oxide film, a silicon nitride film, or a silicon oxynitride film is formed over a substrate 600 having an insulating surface (hereinafter referred to as an insulating substrate). A base insulating film made of is formed. This base insulating film is provided so that alkali metal contained in the insulating substrate does not diffuse into the semiconductor film. As the first layer 601a of the base insulating film, a silicon oxynitride film formed using SiH ₄ , NH ₃ , N ₂ O, and H ₂ as a reactive gas by a plasma CVD method is 10 to 200 nm (preferably 50 to 100 nm). )Form. Here, a silicon oxynitride film with a thickness of 50 nm is formed. Next, as the second layer 601b of the base insulating film, a silicon oxynitride film formed by using a plasma CVD method and using SiH ₄ and N ₂ O as a reaction gas has a thickness of 50 to 200 nm (preferably 100 to 150 nm). Then, they are stacked. Here, a silicon oxynitride film with a thickness of 100 nm is formed. Of course, the carbon nitride composition of the present invention may be formed on the base insulating film.

Next, a first semiconductor film is formed over the base insulating film. As the first semiconductor film, a semiconductor film having an amorphous structure is formed by a sputtering method, an LPCVD method, a plasma CVD method, or the like. In order to obtain a favorable crystal structure, the concentration of impurity elements such as oxygen and nitrogen in the first semiconductor film is preferably reduced to 5 × 10 ¹⁸ atomic / cm ³ or less. Therefore, using a high-purity material gas (raw material gas), and using an ultra-high vacuum-compatible CVD apparatus equipped with a mirror surface treatment (electropolishing treatment) and an oil-free vacuum exhaust system on the inner wall of the film formation chamber Good. In addition, it is preferable that the base insulating film and the first semiconductor film be continuously formed without being exposed to the air because interface contamination can be prevented. In this embodiment, the first amorphous silicon film 602 is formed to a thickness of 10 to 100 nm by a plasma CVD method using a semiconductor material containing silicon as a main component.

  After that, a material 603 including a metal element typified by Ni (including a film state and a liquid layer state) is formed on the first semiconductor film by spin coating, dip coating, plasma CVD, sputtering, and It forms by either method of a vapor deposition method. In this embodiment, a nickel acetate salt solution containing 1 to 100 ppm of Ni in terms of weight is applied by spin coating. At this time, in order to improve the wettability between the first semiconductor film and the nickel acetate salt solution, it is preferable to form an extremely thin oxide film using an ozone-containing aqueous solution. Further, it is preferable to remove this thin oxide film once and form a thin oxide film again with an aqueous solution containing ozone. By forming such a thin oxide film, an aqueous solution (liquid layer) containing a metal element can be uniformly formed on the first semiconductor film.

  Next, heat treatment for crystallizing the first semiconductor film is performed to form a crystalline semiconductor film (which is a crystalline silicon film in this embodiment). Heat treatment methods include furnace annealing using an electric furnace, instantaneous thermal annealing using a halogen lamp, metal halide lamp, xenon arc lamp, carbon arc lamp, high pressure sodium lamp, high pressure mercury lamp, etc. (LRTA method) Alternatively, a gas heating instantaneous thermal annealing method (GRTA method) may be employed.

Further, in order to improve the crystallinity of the first semiconductor film and repair defects remaining in the crystal grains, the first semiconductor film may be irradiated with laser light. As the laser, a continuous wave or pulsed gas laser or a solid laser is used. Examples of gas lasers include excimer laser, Ar laser, and Kr laser. Examples of solid lasers include YAG laser, YVO ₄ laser, YLF laser, YAlO ₃ laser, glass laser, ruby laser, alexandride laser, and Ti: sapphire laser. Can be mentioned.

In crystallization of the first semiconductor film, in order to obtain crystals with a large grain size, it is particularly preferable to use a solid-state laser capable of continuous oscillation and apply the second to fourth harmonics of the fundamental wave. Typically, a second harmonic (532 nm) or a third harmonic (355 nm) of an Nd: YVO ₄ laser (fundamental wave 1064 nm) may be applied.

In the present embodiment, laser light emitted from a continuous wave YVO ₄ laser having an output of 10 W is converted into a harmonic by a non-linear optical element. There is also a method of emitting harmonics by putting a YVO ₄ crystal and a nonlinear optical element in a resonator. Then, the cross-sectional shape of the laser light on the irradiation surface is formed into a rectangular shape or an elliptical shape by the optical system, and the first semiconductor film is irradiated. At this time, the energy density of approximately 0.01 to 100 MW / cm ² (preferably 0.1 to 10 MW / cm ²⁾ is required. Then, scanning is performed by relatively moving the laser light and the first semiconductor film at a speed of about 0.5 to 2000 cm / s.

  A metal element (Ni in this embodiment) remains in the crystalline semiconductor film formed as described above. Therefore, the metal element concentration in the first semiconductor film, that is, the crystalline silicon film is reduced by gettering described below.

  First, an insulating film to be a barrier film is formed over the crystallized first semiconductor film. The barrier film may be processed with ozone water or an aqueous solution in which sulfuric acid, hydrochloric acid or nitric acid and hydrogen peroxide water are mixed to form an oxide film (chemical oxide). In addition, an oxide film is formed by plasma treatment in an oxidizing atmosphere or ultraviolet irradiation in an oxygen-containing atmosphere, or an insulating film including a silicon oxide film is formed by any of a plasma CVD method, a sputtering method, and a vapor deposition method. May be.

  Then, a second semiconductor film serving as a gettering sink is formed on the barrier film with a thickness of 25 to 250 nm. The second semiconductor film is preferably a low-density film because it is removed later.

  After that, by performing heat treatment, Ni which is a metal element in the first semiconductor film is moved while diffusing into the second semiconductor film serving as a gettering sink, and gettering treatment is performed. The heat treatment may be performed using any one of a furnace annealing method, an LRTA method, and a GRTA method. In the case of performing furnace annealing, heat treatment is performed at 450 to 600 ° C. for 0.5 to 12 hours in a nitrogen atmosphere. When the LRTA method is used, the lamp light source for heating is turned on for 1 to 60 seconds, preferably 30 to 60 seconds, and this is repeated 1 to 10 times, preferably 2 to 6 times. The light emission intensity of the lamp light source is such that the semiconductor film is instantaneously heated to 600 to 1000 ° C., preferably about 700 to 750 ° C.

  Note that the first semiconductor film may be crystallized at the same time by heat treatment for performing gettering. That is, crystallization and gettering of the first semiconductor film can be achieved by a single heat treatment, and the number of processes can be reduced.

  Thereafter, the second semiconductor film is removed by wet etching. As a wet etching method, an alkali solution such as an aqueous solution containing hydrazine or tetramethylammonium hydroxide (TMAH) can be used. At this time, the barrier film functions as an etching stopper. Further, after the second semiconductor film is etched, the barrier film may be removed with hydrofluoric acid.

  The first crystallized semiconductor film thus formed, that is, the crystalline semiconductor film, is formed as an elongated rod-like or elongated flat crystal by the action of a metal element, and each crystal may be viewed macroscopically. Growing with a certain direction.

  In order to control a threshold value which is a semiconductor characteristic, boron is preferably added to the crystalline semiconductor film (referred to as channel dope). Thereafter, as shown in FIG. 6B, patterning is performed so as to obtain a desired active layer shape, and island-shaped crystalline semiconductor films are obtained (605a to 605d).

  Next, the surface of the active layer is washed with an etchant containing hydrofluoric acid to form a gate insulating film 606 that covers the active layer. The gate insulating film is formed of an insulating film containing silicon with a thickness of 40 to 150 nm by using a plasma CVD method or a sputtering method. In this embodiment mode, a silicon oxynitride film (composition ratio: Si = 32%, O = 59%, N = 7%, H = 2%) is formed with a thickness of 115 nm by a plasma CVD method. Of course, the gate insulating film is not limited to the silicon oxynitride film, and the carbon nitride composition of the present invention may be used. By forming the base insulating film and the gate insulating film with the same material using the same method, the thermal expansion coefficient becomes equal, and even if the semiconductor film expands due to heat treatment such as activation, film peeling from the interface (Peeling) can be prevented.

  Next, as illustrated in FIG. 6C, a first conductive film 608a with a thickness of 20 to 100 nm and a second conductive film 608b with a thickness of 100 to 400 nm are stacked over the gate insulating film to form a gate electrode 608. Form. In this embodiment, a gate electrode is formed by sequentially stacking a tantalum nitride film with a thickness of 50 nm and a tungsten film with a thickness of 370 nm on the gate insulating film 606.

  Note that the first conductive film and the second conductive film may be formed using an element selected from Ta, W, Ti, Mo, Al, and Cu, or an alloy material or a compound material containing the element as a main component. Alternatively, a semiconductor film typified by a polycrystalline silicon film doped with an impurity element such as phosphorus, or an AgPdCu alloy may be used as the first conductive film and the second conductive film. Further, the present invention is not limited to the two-layer structure. For example, a three-layer structure in which a 50 nm-thickness tungsten film, a 500 nm-thick aluminum and silicon alloy (Al-Si) film, and a 30 nm-thickness titanium nitride film are sequentially stacked. Also good. In the case of a three-layer structure, tungsten nitride may be used instead of tungsten of the first conductive film, or aluminum instead of the aluminum and silicon alloy (Al-Si) film of the second conductive film. A titanium alloy film (Al—Ti) may be used, or a titanium film may be used instead of the titanium nitride film of the third conductive film. Moreover, a single layer structure may be sufficient. In this embodiment mode, a TaN film is used as the first conductive film, and a W film is used as the second conductive film.

Thereafter, patterning is performed in the following procedure to form each gate electrode and each wiring. Using an ICP (Inductively Coupled Plasma) etching method, the etching conditions (the amount of power applied to the coil-type electrode, the amount of power applied to the electrode on the substrate side, the electrode temperature on the substrate side, etc.) are appropriately set. By adjusting, the TaN film and the W film can be etched into a desired tapered shape. As an etching gas, a chlorine-based gas typified by Cl ₂ , BCl ₃ , SiCl _4, CCl _4, etc., a fluorine-based gas typified by CF ₄ , SF _6, NF _3, etc., or O ₂ is appropriately used. be able to.

First, a mask made of a resist (not shown) having a desired shape is formed on the W film. As the first etching conditions, CF ₄ , Cl _2, and O ₂ are used as etching gases, the respective gas flow ratios are 25/25/10 sccm, and 700 W RF (13.56 MHz) power is applied at a pressure of 1 Pa. A 150 W RF (13.56 MHz) power is applied to the electrode on the substrate side (sample stage), and a substantially negative self-bias is applied. Under these etching conditions, only the W film is etched to have a tapered shape with an end angle of 15 to 45 °.

Thereafter, the second etching is performed without removing the resist mask. The second etching condition is that CF ₄ and Cl ₂ are used as etching gases, the respective gas flow ratios are 30/30 sccm, and 500 W RF (13.56 MHz) power is applied to the coil-type electrode at a pressure of 1 Pa. A 20 W RF (13.56 MHz) power is also applied to the electrode on the substrate side (sample stage), and a substantially negative self-bias is applied. Under the second etching conditions, the TaN film of the first conductive film and the W film of the second conductive film are etched to the same extent.

Next, without removing the resist mask, a first doping process is performed in which an impurity element imparting conductivity is added to the semiconductor film using the gate electrode as a mask. The first doping process may be performed by an ion doping method or an ion implantation method. Typically, phosphorus (P) or arsenic (As) is used as the impurity element imparting n-type conductivity. A first impurity region 609 is formed in a self-aligning manner. An impurity element imparting n-type is added to the first impurity region in a concentration range of 1 × 10 ²⁰ to 1 × 10 ²¹ / cm ³ .

Next, a third etching is performed without removing the resist mask. Here, the third etching condition is that CF ₄ and Cl ₂ are used as the etching gas, the respective gas flow ratios are 30/30 sccm, and a 500 W RF (13.56 MHz) is applied to the coil-type electrode at a pressure of 1 Pa. ) Apply power, apply 20 W RF (13.56 MHz) power to the substrate side (sample stage), and apply a substantially negative self-bias.

Thereafter, the fourth etching is performed without removing the resist mask. As the fourth etching condition, CF ₄ , Cl _2, and O ₂ are used as etching gases, the respective gas flow ratios are set to 20/20/20 sccm, and 500 W of RF (13.56) is applied to the coil-type electrode at a pressure of 1 Pa. MHz) power is applied to the electrode, and 20 W of RF (13.56 MHz) power is also applied to the substrate side (sample stage) to apply a substantially negative self-bias. The W film and the TaN film are anisotropically etched by the third etching and the fourth etching. Also, by including oxygen in the etching gas, the etching rate of the W film and the TaN film is differentiated, and the etching rate of the W film is made faster than the etching rate of the TaN film. Although not shown, the gate insulating film not covered with the first conductive layer is etched and thinned. At this stage, a gate electrode, wiring, or the like having a TaN film as a lower layer as the first conductive layer 608a and a W film as an upper layer as the second conductive layer 608b is formed.

Next, after removing the resist mask, a new resist mask is formed on the n-channel TFT and a second doping process is performed. By the second doping treatment, a second impurity region 610 in which an impurity element imparting p-type conductivity (boron or the like) is added to the semiconductor film forming the semiconductor film for forming the p-channel TFT is formed. Note that an impurity element imparting p-type conductivity is added to the second impurity region 610 in a concentration range of 1 × 10 ²⁰ to 1 × 10 ²¹ / cm ³ . Note that the second impurity region is a region to which phosphorus (P) is added in the previous step (n ⁺ region), but the concentration of the impurity element imparting p-type is added 1.5 to 3 times the concentration. Therefore, the conductivity type is p-type.

  Note that in this embodiment, a low-concentration impurity region (LDD region) or a low-concentration impurity region (GOLD region) overlapping with the gate electrode 608 may be formed as appropriate.

  Through the above steps, impurity regions having n-type or p-type conductivity are formed in each semiconductor film. Then, after the impurity region is formed, heat treatment, intense light irradiation, or laser light irradiation is performed to activate the impurity element. Simultaneously with activation, plasma damage to the gate insulating film and plasma damage to the interface between the gate insulating film and the semiconductor film can be recovered. In particular, in an atmosphere of room temperature to 300 ° C., the impurity element is activated by irradiating an excimer laser from the front side or the back side. Alternatively, the YAG laser may be activated by irradiation with the second harmonic, and the YAG laser is a preferable activation means because it requires less maintenance.

  Next, as shown in FIG. 6D, a carbon nitride composition 612 to be a first interlayer insulating film is formed to a thickness of 100 nm at a reaction temperature of 20 to 30 ° C. by plasma CVD. Since the carbon nitride composition contains a lot of hydrogen and has high stress relaxation properties, it can be formed with good step coverage. Thereafter, dangling bond termination of the semiconductor film can be performed by hydrogen annealing or hydrogen plasma treatment in a vertical furnace annealing furnace. At this time, an effect of metal sintering and a recovery effect of plasma damage by etching can be expected.

  Thereafter, as shown in FIG. 6E, a second interlayer insulating film 613 made of an inorganic insulating material or an organic insulating material containing silicon is formed over the first interlayer insulating film. As the organic insulator material, a positive photosensitive organic resin or a negative photosensitive organic resin can be used. Note that in the case where a photosensitive organic resin is used, a first opening having a curvature can be formed by etching the photosensitive organic resin by an exposure process in a photolithography process. However, when a positive photosensitive organic resin is used for the second interlayer insulating film, since the positive photosensitive resin is colored brown, the photosensitive organic resin needs to be decolored after etching. In the case where the second interlayer insulating film is formed using the photosensitive organic resin, an insulating film containing nitrogen may be formed on the interlayer insulating film in order to prevent moisture release from the interlayer insulating film. A composition may be formed. Note that in this embodiment, as the second interlayer insulating film, a silicon oxide film is formed with a thickness of 1 μm by a plasma CVD method.

  Next, the second interlayer insulating film 613, the first interlayer insulating film 612, and the gate insulating film 606 are sequentially etched to form openings. The etching process at this time may be a dry etching process or a wet etching process. In this embodiment, an opening (contact) having a smooth taper (angle) is formed by dry etching. After the opening is formed, a metal film is formed on the second interlayer insulating film and in the opening, and the metal film is etched to form the source and drain electrodes 615, wiring (second wiring), and the like. . As the metal film, a film made of an element of aluminum (Al), titanium (Ti), molybdenum (Mo), tungsten (W), or silicon (Si) or an alloy film using these elements may be used.

In the present embodiment, the titanium film (Ti) / silicon-aluminum alloy film (Al—Si) / titanium film (Ti) are laminated to 100/350/100 nm, respectively, and then patterned and etched into a desired shape to form a source. An electrode, a drain electrode, and a second wiring are formed. Thereafter, an electrode (electrode serving as an anode or a cathode of the light-emitting element) 616 is formed. A transparent conductive film such as ITO or SnO ₂ can be used for the electrode. In this embodiment mode, an electrode 616 is formed by forming an ITO film with a thickness of 110 nm and etching it into a desired shape.

  The active matrix substrate provided with the carbon nitride composition of the present invention is completed through the above steps. Note that the carbon nitride composition may be used for any of insulating films such as a base insulating film, an interlayer insulating film, a protective film, and a passivation film formed on an active matrix substrate. In particular, when a carbon nitride composition is used for the interlayer insulating film, the nitrogen content can be increased and the relative dielectric constant can be lowered, and delay of circuit operation can be expected to be prevented.

  Although an example of a top-gate thin film transistor in which a gate electrode is provided over a semiconductor film has been described in this embodiment, a bottom-gate thin film transistor in which a gate electrode is provided under a semiconductor film may be used.

  In addition, the case where a polycrystalline semiconductor film is formed by crystallizing a semiconductor film to form a channel formation region of a thin film transistor has been described. However, a carbon nitride composition can be used even when a polycrystalline semiconductor film is formed on a quartz substrate. Needless to say. Furthermore, the carbon nitride composition can be used for an interlayer insulating film of an amorphous thin film transistor using an amorphous semiconductor film.

  Furthermore, since the carbon nitride composition of the present invention can be formed preferably at 20 to 30 ° C., the thin film transistor formed on a plastic (resin) substrate such as polycarbonate, polyarylate, polyether sulfone, polytetrafluoroethylene, etc. It can also be used as an interlayer insulating film. When a thin film transistor is formed over a plastic substrate, the device becomes light and difficult to break. In addition to the plastic substrate, a glass substrate, a ceramic substrate, or the like may be thinned to increase flexibility. Hereinafter, such a thin and flexible plastic substrate or ceramic substrate is also referred to as a film substrate.

(Embodiment 5)
In this embodiment, a liquid crystal display device provided in an active matrix substrate formed as in Embodiment 4 will be described with reference to FIGS.

  FIG. 7A is a top view of the liquid crystal display device, in which a signal line driver circuit 1301, a scan line driver circuit 1303, and a pixel portion 1302 are provided over a first insulating substrate 1310.

  FIG. 7B is a cross-sectional view taken along the line AA ′ of the liquid crystal display device. The signal line driver circuit 1301 includes a CMOS circuit having an n-channel TFT 1323 and a p-channel TFT 1324 over a first insulating substrate 1310. Is provided. Note that a thin film transistor (TFT) forming the signal line driver circuit or the scan line driver circuit may be formed using a CMOS circuit, a PMOS circuit, or an NMOS circuit. In this embodiment mode, a driver integrated type in which a signal line driver circuit and a scan line driver circuit are formed over a substrate is shown; however, this is not necessarily required, and the driver can be formed outside the substrate.

  In addition, an interlayer insulating film having a switching TFT 1311 and a storage capacitor 1312 connected to the pixel electrode, covering the switching TFT and the storage capacitor, and having an opening at a predetermined position, and a pixel portion 1302 are shown. .

  A first interlayer insulating film 1313 (partially shown) made of the carbon nitride composition of the present invention is provided to cover the semiconductor film on which the gate electrode is formed. A second interlayer insulating film 1314 is provided on the first interlayer insulating film, an alignment film 1317 is provided on the second interlayer insulating film 1314, and the alignment film is rubbed.

  A second insulating substrate 1304 is prepared as a counter substrate. The second insulating substrate 1304 is provided with an RGB color filter 1330, a counter electrode 1316, and an alignment film 1317 subjected to rubbing treatment.

  A polarizing plate 1331 is provided on the first and second insulating substrates, and the first and second insulating substrates are bonded to each other with a sealant 1305. As the sealant, a thermosetting resin, an ultraviolet curable resin, or a curable resin having both functions may be used.

  A liquid crystal material 1318 is provided between the first and second insulating substrates. The liquid crystal material is formed between the first and second insulating substrates by a vacuum injection method or a dropping method.

  Although not shown, a spacer is appropriately provided to hold the first and second insulating substrates. The spacer may be a spherical spacer or a columnar spacer.

  And wiring and a flexible printed circuit board (FPC) are connected by anisotropic conductive resin (ACF), and a video signal and a clock signal are received. Note that care must be taken when connecting FPCs so that cracks do not occur.

  In this manner, a liquid crystal display device including a TFT having the carbon nitride composition of the present invention is completed. The carbon nitride composition of the present invention can be used for any insulating film included in a TFT.

  Note that in this embodiment, a film substrate can be used as the insulating substrate. In this case, a thinner and lighter liquid crystal display device can be provided.

(Embodiment 6)
In this embodiment mode, in the case of using the carbon nitride composition of the present invention for a protective film on a cathode or an anode in a display device having a light emitting element including a TFT manufactured on a film substrate, FIG. 8 is used. I will explain.

  FIG. 8A shows a top view of a display device having a light-emitting element. A signal line driver circuit 1201, a scan line driver circuit 1203, and a pixel portion 1202 are provided over a first film substrate 1210.

  FIG. 8B is a cross-sectional view taken along line AA ′ of a display device having a light-emitting element. A signal including a CMOS circuit having an n-channel TFT 1223 and a p-channel TFT 1224 on a first film substrate 1210. A line drive circuit 1201 is shown. Further, the TFT forming the signal line driver circuit or the scanning line driver circuit may be formed of a CMOS circuit, a PMOS circuit, or an NMOS circuit. In this embodiment mode, a driver integrated type in which a signal line driver circuit and a scan line driver circuit are formed over a substrate is shown; however, this is not necessarily required, and the driver may be formed outside the substrate.

  In addition, the switching TFT 1211 and the current control TFT 1212 are provided. The insulating film 1214 that covers the switching TFT and the current control TFT and has an opening at a predetermined position is connected to one wiring of the current control TFT 1212. A light-emitting element including a first electrode 1213, a light-emitting layer (hereinafter referred to as an organic light-emitting layer) 1215 provided with an organic material provided over the first electrode, and a second electrode 1216 provided so as to face each other A pixel portion 1202 having 1218 and a protective film 1217 provided to prevent deterioration of the light-emitting element due to moisture, oxygen, or the like is shown. Note that the light-emitting layer included in the light-emitting element may include an inorganic material or a mixed material of an organic material and an inorganic material.

  In this embodiment mode, a carbon nitride composition is used for the protective film 1217. That is, the carbon nitride composition of the present invention is preferably formed at 20 to 30 ° C. on the protective film formed after the formation of the organic light emitting layer having low heat resistance to prevent deterioration due to heat. In addition, when a protective film is formed on a semiconductor element formed on a film substrate as in this embodiment, the use of the carbon nitride composition of the present invention can prevent deformation of the film substrate.

  Since the first electrode 1213 is connected to the drain of the current control TFT 1212, at least the lower surface of the first electrode 1213 is made of a material that can make ohmic contact with the drain region of the semiconductor film, and the organic light emitting layer It is desirable to use a material having a high work function on the surface in contact with the surface. For example, when a three-layer structure of a titanium nitride film, a film containing aluminum as a main component, and a titanium nitride film is used, the resistance as a wiring is low and the function can be achieved so that a good ohmic contact is obtained. Further, the first electrode 1213 may be a single layer of a titanium nitride film, or a stack of three or more layers may be used. In addition, when a transparent conductive film is used as the first electrode 1213, a display device having a dual emission type light emitting element can be manufactured.

  The insulating film 1214 may be formed using an organic resin film or an insulating film containing silicon. Here, the insulating film 1214 is formed using a positive photosensitive acrylic resin film.

  Note that it is preferable that a curved surface having a curvature be formed at the upper end portion or the lower end portion of the insulating film 1214 in order to improve the step coverage of an electrode or an organic light emitting layer to be formed later. For example, when positive photosensitive acrylic is used as the material of the insulating film 1214, only the upper end portion of the insulating film 1214 may have a curved surface having a curvature radius (0.2 μm to 3 μm). As the insulating film 1214, either a negative photosensitive resin that becomes insoluble in an etchant by light or a positive photosensitive resin that becomes soluble in an etchant by light can be used.

  The insulating film 1214 may be covered with an insulating film containing nitrogen. An aluminum nitride film, an aluminum nitride oxide film, or a silicon nitride film obtained by using the carbon nitride composition of the present invention for this insulating film, or a film forming apparatus using a sputtering method (DC method or RF method) or remote plasma Such an insulating film containing silicon nitride or silicon nitride oxide as a main component or a thin film containing carbon as a main component can be used.

  Over the first electrode 1213, an organic light emitting layer 1215 that can obtain RGB light emission is selectively formed by a vapor deposition method using a vapor deposition mask or an ink jet method. A second electrode 1216 is formed on the organic light emitting layer 1215.

  In the case where the light emitting element 1218 emits white light, it is necessary to provide a color filter including a colored layer and a BM (black matrix).

  The second electrode 1216 is connected to the connection wiring 1208 through an opening (contact) provided in the insulating film 1214 in the connection region, and the connection wiring 1208 is formed of a flexible printed circuit board by anisotropic conductive resin (ACF). (FPC) 1209 is connected. Then, a video signal and a clock signal are received from the FPC 1209 serving as an external input terminal. Although only the FPC is shown here, a printed wiring board (PWB) may be attached to the FPC.

  Also, when the ACF is bonded by pressurization or heating, care is taken not to cause cracks due to the flexibility of the film substrate and softening due to heating. For example, a highly rigid substrate may be disposed as an auxiliary in the adhesion region.

  In addition, a sealant 1205 is provided on the peripheral edge of the first film substrate, and is bonded to the second film substrate 1204 and sealed. The sealing material 1205 is preferably an epoxy resin.

  In this embodiment, a plastic substrate made of FRP (Fiberglass-Reinforced Plastics), PVF (Polyvinyl Fluoride), Mylar, polyester, acrylic, or the like is used as a material constituting the second film substrate 1204 in addition to a glass substrate or a quartz substrate. Can be used.

  Although not shown, the film substrate is made of an organic material such as polyvinyl alcohol or an ethylene vinyl alcohol copolymer or an inorganic material such as polysilazane, aluminum oxide, silicon oxide, silicon nitride, or the like so that water and oxygen do not enter. It is good to cover with the barrier film which consists of lamination.

  Further, a protective layer may be provided on the film substrate in order to protect from chemicals in the manufacturing process. As the protective layer, an ultraviolet curable resin or a thermosetting resin can be used.

  As described above, a display device having a light emitting element including a carbon nitride composition provided on a film substrate is completed.

(Embodiment 7)
The active matrix substrate provided with the carbon nitride composition of the present invention can be applied to various electronic devices. Examples of the electronic device include a portable information terminal (a mobile phone, a mobile computer, a portable game machine, an electronic book, etc.), a video camera, a digital camera, a goggle type display, a display display, a navigation system, and the like. Specific examples of these electronic devices are shown in FIGS.

  FIG. 9A illustrates a display (display device), which includes a housing 4001, an audio output portion 4002, a display portion 4003, and the like. A display portion 4003 including a light-emitting element or a liquid crystal material formed over an active matrix substrate including a carbon nitride composition can be completed. The display device includes all information display devices such as a personal computer, a TV broadcast reception, and an advertisement display.

  FIG. 9B illustrates a mobile computer, which includes a main body 4101, a stylus 4102, a display portion 4103, operation buttons 4104, an external interface 4105, and the like. A display portion 4103 including a light-emitting element and a liquid crystal material formed over an active matrix substrate including a carbon nitride composition can be completed.

  FIG. 9C illustrates a game machine, which includes a main body 4201, a display portion 4202, operation buttons 4203, and the like. A display portion 4202 including a light-emitting element and a liquid crystal material formed over an active matrix substrate including a carbon nitride composition can be completed. FIG. 9D illustrates a mobile phone, which includes a main body 4301, an audio output portion 4302, an audio input portion 4303, a display portion 4304, operation switches 4305, an antenna 4306, and the like. A display portion 4304 including a light-emitting element or a liquid crystal material formed over an active matrix substrate including a carbon nitride composition can be completed.

  FIG. 9E illustrates an electronic book reader (electronic book), which includes a display portion 4401 and the like. A display portion 4401 including a light-emitting element and a liquid crystal material formed over an active matrix substrate including a carbon nitride composition can be completed.

  As described above, the applicable range of the present invention is so wide that the present invention can be used for electronic devices in various fields. In particular, when the insulating substrate of the active matrix substrate is a flexible substrate and is thin and lightweight, it is very effective for the electronic devices shown in FIGS.

Example 1
In this example, the results of composition analysis of a carbon nitride composition formed by plasma CVD using C ₂ H ₂ / N ₂ , C ₂ H ₄ / N _2, and C ₂ H ₄ / NH ₃ gases. Indicates.

  Table 1 shows the results of composition analysis (NRA / HFS) in the carbon nitride compositions of Samples A to C having different production conditions. The film thickness of Samples A and B was about 100 nm, and the film thickness of Sample C was about 10 nm.

  From this example, it can be seen that the hydrogen concentration ratio (hydrogen ratio) of the carbon nitride composition is about 35 to 40 atomic% (strictly 35.8 to 40.4 atomic%). The hydrogen ratio of a general SiN film is about 25 atomic%, and it can be seen that the hydrogen ratio of the carbon nitride composition of the present invention is quite high. The carbon concentration ratio (carbon ratio) of the carbon nitride composition is about 40 to 50 atomic% (strictly 21.4 to 50.8 atomic%, but 21.4 atomic% seems to have an excessive measurement error). The nitrogen concentration ratio (nitrogen ratio) is about 10 to 20 atomic% (strictly, it is 13.4 to 42.7 atomic%, but 42.7 atomic% seems to have an excessive measurement error). .

The result of tensile stress of sample A was 1.5 × 10 ⁹ dyne / cm ² .

FIG. 10 shows the result of Raman spectrum measurement using 514.5 nm as excitation light for the sample B formed on the silicon wafer. From FIG. 10, no peak due to the crystal structure could be confirmed, and fluorescence was confirmed. The peak in the vicinity of 900 to 1000 cm ⁻¹ is a peak due to the silicon wafer (see reference). From the above, it can be seen that the carbon nitride composition of Sample B has an amorphous state. In DLC having general crystallinity, a peak can be observed in the vicinity of 1600 cm ⁻¹ .
In addition, since fluorescence is observed when the network structure is changed to a linear structure, it is possible that the network structure is reduced in the carbon nitride composition of Sample B.

Next, FIG. 11 shows the result of ESCA (Electron Spectroscopy for Chemical Analysis) analysis performed on the sample B. FIG. 11 is a graph in which waveforms are separated in the range of 280 to 295 eV of binding energy (Binding Energy). The waveform C1 is C-C, C = C, C-H, the waveform C2 is C-N, C-O, the waveform C3 is C = N, C = O, the waveform C4 is O = C-O, and the waveform C5 is This is due to the shake-up peak accompanying the π → π ^* transition. When each waveform is viewed in Area%, they are C1: 75.37%, C2: 17.01%, C3: 7.60%, C4: 0.02%, and C5: 0%. From the above, it can be seen that Sample B has a bond resulting from C-N or C = N.

  Since the carbon nitride composition of the present invention formed as described above has high stress relaxation properties, it becomes possible to form films on substrates and semiconductor elements having various shapes.

(Example 2)
In this example, the desorption temperature of hydrogen was measured by TDS (Thermal Desorption Spectrocopy) analysis of the carbon nitride composition of the present invention.

TDS analysis is to obtain a mass spectrum of desorbed components from a sample for each temperature by mass analysis of gas molecules emitted while heating the sample in high vacuum with infrared heating. The background vacuum degree of the measuring apparatus is 10 ⁻⁹ Torr, and sensitivity for extremely small amounts of components can be expected. In this example, EMD-WA1000S manufactured by ESCO was used.

  In this example, the results of comparing samples A and B, which are the carbon nitride compositions of the present invention shown in Table 1, with a silicon nitride (SiN) film and a silicon nitride oxide (SiNO) film formed by a plasma CVD method are shown. As shown in FIG.

  From the results shown in FIG. 5, the silicon nitride film and the silicon nitride oxide film have a high hydrogen release amount with a peak at around 450 ° C. On the other hand, samples A and B, which are the carbon nitride compositions of the present invention, increase in hydrogen strength from 400 ° C. to 550 ° C., but overall have low hydrogen strength. That is, even when heated at 450 ° C. to 500 ° C. or more, and even near 600 ° C. (about 450 ° C. to 600 ° C.), the amount of released hydrogen is extremely small. Therefore, it is considered that the carbon nitride composition has high hydrogen bonding strength and the film is stable.

  As described above, the carbon nitride composition of the present invention hardly releases hydrogen despite being subjected to heat treatment. As a result, the film hardly peels off and is useful as a protective film or insulating film having adhesion.

The figure which shows the CVD apparatus which forms the carbon nitride composition of this invention. The figure which shows the CVD apparatus which coats the carbon nitride composition of this invention. The figure which shows the CVD apparatus which forms the carbon nitride composition of this invention. The figure which shows the CVD apparatus which forms the carbon nitride composition of this invention. The figure which shows the result of the TDS measurement with respect to the carbon nitride composition of this invention. 4A and 4B illustrate a manufacturing process of a thin film transistor using the carbon nitride composition of the present invention. FIG. 6 shows a liquid crystal display device provided with the thin film transistor of the present invention. 4A and 4B each illustrate a display device including a light-emitting element including a thin film transistor of the present invention. FIG. 14 illustrates an example of an electronic device of the invention. The figure which shows the measurement result by the Raman spectroscopy with respect to the carbon nitride composition of this invention. The figure which shows the measurement result by the ESCA analysis with respect to the carbon nitride composition of this invention.

Claims (6)

Form a base insulating film,
Forming a crystalline silicon film in contact with the base insulating film;
Forming a gate insulating film in contact with the crystalline silicon film;
Forming a gate electrode on the gate insulating film;
Impurity regions are formed by doping an impurity element into the crystalline silicon film using the gate electrode as a mask,
Forming a first interlayer insulating film covering the gate electrode;
Forming a second interlayer insulating film on the first interlayer insulating film;
Feel the underlying insulating film, the gate insulating film and the first interlayer insulating film which has a carbon nitride composition, the carbon nitride composition using a carbide gas, a mixed gas having a nitrogen or nitride gas A method for manufacturing a semiconductor device, wherein the semiconductor device is formed at 100 ° C. or lower by a phase growth method. Oite to claim 1,
The method for manufacturing a semiconductor device, wherein the carbon nitride composition has 30 to 45 atomic% of hydrogen. In claim 1 or 2 ,
The method of manufacturing a semiconductor device, wherein the carbon nitride composition is formed at 20 ° C. to 30 ° C. In any one of Claims 1 thru | or 3 ,
The method for manufacturing a semiconductor device, wherein the carbide gas is C ₂ H ₂ or C ₂ H ₄ . In any one of Claims 1 thru | or 4 ,
The method for manufacturing a semiconductor device, wherein the nitride gas is NH ₃ . In any one of Claims 1 thru | or 5 ,
The method for manufacturing a semiconductor device, wherein the vapor phase growth method uses any one of a high-frequency discharge plasma CVD method, a microwave plasma CVD method, and an ECR plasma CVD method.

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